QUALITY ASSESSMENT OF SEA LEVEL DATA by the UH SEA LEVEL CENTER/NATIONAL OCEANOGRAPHIC DATA CENTER JOINT ARCHIVE FOR SEA LEVEL updated: 09 Apr 2019 Station : Christmas-B Latitude: 01 58.9N Country : Republic of Kiribati Longitude: 157 28.3W JASL # : 011B Time Meridian: LINT (GMT + 14 hr) GLOSS # : 146 Originator #: 011 NODC #: 70151701 Contributor : UH Sea Level Center 1000 Pope Rd. MSB 317 Honolulu, Hawaii 96822 Originator : Dept. of Oceanography University of Hawaii 1000 Pope Rd. MSB 317 Honolulu, Hawaii 96822 Original Data: digital Instrmnt Type: 1. (1974-2/1991) Leupold and Stevens Analog-to-Digital Recorder (ADR); 2. (11/1982-11/2006) Handar Encoder 436A (ENC) 3. (12/1988-11/2006) Handar Encoder 436B (ENB) with datalogger (ENO) starting 12/1994 4. 11/2006- Radar (RAD), Vega Vegapuls 62 5. 11/2006- Pressure transducer (PRS) 6. 09/2009- Radar, Sutron RLR (RA2) Primary channel used in JASL set: 1974-1990: ADR 1991-1997: ENC 1998-11/2006: ENB 11/2006-2014: RAD 2015-2018: RA2 *short gaps in primary channel filled with other channels as available; see UHSLC for specific dates Digitzd Intvl: 15 (ADR,ENB,ENO), 3 or 4 (ENC) minutes, 3 min (RAD) 2 min (PRS); 3 min (RA2) Present Data : Hourly, daily, and monthly values obtained by: Hourly : (pre-1987) Nine-point triangular filter centered on the hour with respective periods of the 95, 50, and 5% amplitude point of the filter response at 623.6, 177.0, and 103.7 minutes;(1987+) three-point Hanning filter centered on the hour Daily : 119-point convolution filter (Bloomfield, 1976) centered on noon applied to the hourly data with respective periods of the 95, 50, and 5% amplitude points at 124.0, 60.2, and 40.2 hours Monthly: Simple average of all daily values; calculated if 7 or fewer days are missing Span of data : 06 Feb 1974 - 31 Dec 2018 Gaps > 1 mon : 12 Mar - 7 May 1976; 21 Mar - 15 May 1978; 21 Jul - 11 Oct 1979;02 Feb - 08 Jun 1996; 01 Aug 2003 - 06 Oct 2003;02 Apr 2007 - 14 Jun 2007 07 May 2008 - 03 Dec 2008;09 Apr 2011 - 09 May 2011 31 May 2015 - 01 Jan 2016;09 Jan 2016 - 01 Jan 2017 Time Refernce: GMT (hours 00-23) Space-filler Flag :-9999 Units : millimeters Missing Data Flag : 9999 Existing : Yes Operational : Yes Sat. Trans. : Yes Distribution : 1974-2018 Refernce Levl: Heights are referred to the station tide staff zero, which is linked to land-based benchmarks. This reference zero is unique to this station and is not an official datum (chart, national, etc.) and is not relative to local tidal parameters, such as mean lower low water. See the Originators for benchmark descriptions, maps, and the geodetic levelling history. Comment : The daily and monthly means reveal no apparent changes in the reference level and agree with Kanton. This series is distinguished from Christmas-A because the data are not linked to a common datum. There is timing offset on order of 5-15 minutes 2003-11/2006. The local time zone is the same as Honolulu plus one day. The JASL update of 09 Apr 2019 replaces 01 Jan 2016 - 05 Sep 2017. CI MISSING REPLACED GAPS QUESTIONABLE YEAR (%) DATA OR BAD DATA FLUCTUATIONS ---- --- -------------------- --------------- -------------------- 1974 90 364-365 (01)041-(15)041 117,233,263-264,282, (11)093-(01)094 307,316 (09)213-(08)214 (17)216-(04)217 (15)335-(00)336 1975 98 1,117-122 (15)028-(02)029 39-46,56-59,69-74, 84-90 1976 84 72-128 none none 1977 100 none none 124-138,150-152 1978 74 80-135,267-269, none 321 278-282,292-296, 299-319,322-323, 328-330 1979 74 11-13,131-136, none 102-104 189-192,202-283 1980 98 64-65,113-116, none 73-79,82,84,94, 156-158 103-110 1981 90 237-264 none none 1982 96 294-308 none none 1983 100 none none none 1984 100 none none none 1985 100 none none none 1986 100 none none none 1987 100 none none none 1988 100 none none none 1989 100 none none none 1990 100 none none none 1991 98 322-329 none none 1992 99 155-157 none none 1993 100 none none none 1994 100 none none none 1995 100 none none none 1996 66 34-160 none none 1997 100 none none none 1998 100 none none none 1999 100 none none none 2000 100 none none none 2001 99 155-157 none none 2002 100 none none none 2003 82 213-279 none see comment above 2004 100 none none see comment above 2005 100 none (01)169-(08)169 see comment above (19)170-(03)171 (20)171-(04)172 (22)173-(06)174 (09)174-(16)174 (18)174-(03)175 (06)181-(13)181 (10)183-(21)183 (05)188-(12)188 (22)188-(05)189 (02)190-(14)190 (00)359-(09)359 (03)362-(12)362 (08)365-(17)365 2006 100 none (06)003-(19)003 see comment above (00)005-(07)005 2007 80 92-165 (15)028-(23)028 none (02)261-(23)261 (01)267-(23)267 (04)268-(23)268 (01)269-(23)269 2008 42 128-338 none none 2009 100 none none none 2010 100 none (19)315-(02)316 none (13)332-(23)332 2011 86 99-129,157-179 (11)181-(18)181 none (15)239-(02)240 (10)240-(18)240 2012 99 81-83 none none 2013 100 none (00)065-(16)065 none (13)174-(23)174 (01)235-(08)235 2014 100 none (15)178-(23)178 none 2015 41 151-365 (08)001-(20)001 none 2016 2 9-366 (19)006-(02)007 none 2017 99 1 none none 2018 100 none (21)233-(13)234 none